Modern digital computer systems often use modulator/de-modulator (modem) devices to communicate remotely over telephone lines and other switchable or dial-up channels. As personal computers and modems become less expensive, more and more personal computers in general, and portable computers in particular, include modem devices. Modem use also increases as the use of remote communication services via computer, such as electronic mail, the Internet and on-line services becomes more prevalent. With more computers including modems, it becomes more important that they become easier to use.
In addition to computers, "info-tainment" devices are being designed that rely on remote communications services to provide the user with desired information such as stock quotes or news, or with desired entertainment such as games that are down-loaded to the device from a server or that are played interactively by multiple remote players.
At the same time, the range of available communication lines is increasing. For regular land-line connections on the Public Switched Telephone Network (PSTN), the currently prevalent standards are V.32bis or V.34. For cellular phone communication lines, the protocols MNP10, ETC. or TX-CEL are being used. Thus, to access different communications lines, a single modem may require switching between multiple communication lines and protocols, or a single computing or info-tainment apparatus may require switching between multiple modems. Such line and modem switching should be easy and should not involve the user in the computer system's implementation details.
At the same time, portable computing and info-tainment apparatuses are becoming more prevalent. Particularly in the case of a portable apparatus, it is desirable to have both a standard modem device for land-line telephone communication, as well as a cellular-capable modem device for communication while traveling, or while at remote sites. Typically, the cellular-capable modem would be removable from the portable computing device, due to its size and weight. In such a situation, it is desirable that the user not be required to undertake a complex series of actions on his portable apparatus to switch which modem is currently being used.
Further, a typical computing or info-tainment apparatus includes a wide variety of different application programs that require communication services, including but limited to: electronic mail, Internet browsing, news, stock quotes, and on-line financial services. Each application program may have a different set of commands or set-up tables by which the user specifies the current modem and the sequence of numbers to dial to establish communications. Each application program may keep its own "phone book" of frequently dialed numbers, and its own set of current modem selection and control parameters. It is not uncommon that these essential parameters are expressed in terms of the low-level details that implement the modem's interface to the computing system, such as COM ports and modem initialization strings. The user of a prior-art computing device may be expected to operate these various user interfaces as needed to accommodate different modems, different communications lines, and calls originating from different locations.
Further, in order to access a communication service, the modem may have to dial a prefix to get an outside line, dial an account code or phone card number, or dial an area code. If the user takes his portable computing device to a new area code, or if he plugs his modem into a line that requires a different prefix to access an outside line, then the modem is likely to dial incorrectly, unless the user explicitly changes the area code and access prefix values. This may have to be done for every entry in the various telephone books that he is going to use at this location. Further, as he changes locations, these changes to his telephone book entries may have to be repeatedly undone and redone.